Liquid crystal display device

ABSTRACT

A plurality of grooves ( 28 ) are provided in a surface of the array substrate ( 20 ) facing the liquid crystal layer ( 50 ) to extend along a sealing material, and are spaced apart from each other in a width direction of the sealing material. An alignment film ( 27 ) covers surfaces of some or all of the grooves located from a midway portion of the sealing material in a width direction thereof toward a display region (D), and is in contact with the sealing material, and part of the sealing material located from the midway portion in the width direction in a direction away from the display region is directly in contact with the array substrate without the alignment film being provided between the seal material and the array substrate.

TECHNICAL FIELD

The present invention relates to liquid crystal display devices, inparticular, a structure for controlling a region of a picture-frameregion of a display panel to which an alignment film is applied.

BACKGROUND ART

Liquid crystal display devices can have a smaller thickness and lowerpower consumption. Therefore, the liquid crystal display devices arewidely used as displays of television sets, OA equipment (e.g., personalcomputers), portable electronic devices (e.g., mobile phones and smartphones), and cockpits of vehicles, aircrafts, etc.

A liquid crystal display device includes a display panel and a backlightunit attached to a back surface of the display panel. The display panelincludes an array substrate including switching elements (e.g., thinfilm transistors, etc.), a counter substrate facing the array substrate,and a sealing material bonding the array substrate and the countersubstrate to each other. A liquid crystal material is enclosed in aspace between the two substrates. The counter substrate is slightlysmaller than the array substrate. Therefore, a terminal region of thearray substrate is exposed. A drive circuit is mounted to the exposedterminal region.

The display panel includes a display region for displaying an image anda non-display region surrounding the display region.

An alignment film is provided on a surface of the array substratecontacting a liquid crystal layer to cover at least the display region.Similarly, an alignment film is provided on a surface of the countersubstrate contacting the liquid crystal layer to cover at least at leastthe display region

The alignment film may be formed by performing rubbing treatment on asurface of a resin film of polyimide, etc. formed by flexographicprinting, inkjet printing, etc. To form the resin film of polyimide,etc., inkjet printing is preferably employed for the following reasons:the resin film can be drawn directly on the substrate; contamination canbe reduced due to the non-contact process; the amount of solutionconsumed can be reduced; the time required can be reduced; etc.

Incidentally, when inkjet printing is used to form the alignment film, aresin which is a material having a lower viscosity than whenflexographic printing is used is used as a material of the alignmentfilm. Therefore, the material of the alignment film tends to leak andspread out around a region (display region) in which the alignment filmshould be printed. Therefore, if the non-display region around thedisplay region is so small that a large space cannot be ensured betweenthe display region and a sealing member region, the alignment film maybe formed to reach the sealing member region. In this case, theadherence between the sealing member and the alignment film isinsufficient, and therefore, the gap between the two substrates cannotbe completely sealed, so that the liquid crystal material of the liquidcrystal layer may leak.

In order to solve the above problem, PATENT DOCUMENT 1 describes aliquid crystal display device including a groove portion, wherein thegroove portion is provided in a generally annular region which islocated outside the display region and inside the region to be providedwith the sealing member, and the groove portion extends long along theperiphery of the display region. With this configuration, even if theliquid resin material applied by inkjet printing spreads out of thedisplay region, the groove portion can prevent the resin material fromfurther spreading, whereby the spread outside the display region of thealignment film can be reduced or prevented. PATENT DOCUMENT 1 furtherdescribes a configuration in which a conductive film such as an ITO filmis provided on a surface of the groove portion. The liquid resinmaterial which is a material of the alignment film has a poor wettingproperty with respect to the ITO film. Therefore, with thisconfiguration, the groove portion can reduce or prevent the spreadoutside the display region of the alignment film.

CITATION LIST Patent Document

PATENT DOCUMENT 1: Japanese Unexamined Patent Publication No.2007-322627

SUMMARY OF THE INVENTION Technical Problem

In recent years, in particular, for portable electronic devices, thewidth of a picture-frame region around a display region needs to bereduced in order to fulfill demands for both reducing the total size ofa display device and increasing the display region.

In order to prevent the alignment film from reaching a region in whichthe sealing material is to be formed and from causing insufficientadhesiveness between the sealing material and the substrate, PATENTDOCUMENT 1 describes that a structure (a groove portion extending longin a direction along the periphery of the display region) to prevent thespread of the alignment film is formed so as not to overlap the sealingmaterial region. However, when the structure to prevent the spread ofthe alignment film is provided so as not to overlap the seal region, thepicture-frame region is increased by the structure.

It is an object of the present invention to provide a liquid crystaldisplay device having a reduced picture-frame width without reducing theadhesiveness of a sealing material of a display panel.

Solution to the Problem

To achieve the object, an example liquid crystal display device of thepresent invention includes: an array substrate; a counter substratefacing the array substrate; a sealing material which is provided outsidea display region and by which the array substrate is bonded to thecounter substrate; a liquid crystal layer in a region surrounded by thesealing material between the array substrate and the counter substrate;and alignment films each provided on a surface of a corresponding one ofthe array substrate and the counter substrate facing the liquid crystallayer to cover an area including the display region. A plurality ofgrooves are provided in the surface of the array substrate facing theliquid crystal layer to extend along the sealing material, and arespaced apart from each other in a width direction of the sealingmaterial, each alignment film covers surfaces of some or all of thegrooves located from a midway portion of the sealing material in a widthdirection thereof toward the display region, and is in contact with thesealing material, and part of the sealing material located from themidway portion in the width direction in a direction away from thedisplay region is directly in contact with the array substrate withoutthe alignment film being provided between the seal material and thearray substrate.

Preferably, in the example liquid crystal display device of the presentinvention, a plurality of grooves are provided in the surface of thecounter substrate facing the liquid crystal layer to extend along thesealing material, and are spaced apart from each other in a widthdirection of the sealing material, each alignment film covers surfacesof some or all of the grooves in the array substrate and the countersubstrate located from the midway portion of the sealing material in thewidth direction thereof toward the display region, and is in contactwith the sealing material, and the part of the sealing material locatedfrom the midway portion in the width direction in a direction away fromthe display region is directly in contact with the array substrate andthe counter substrate without the alignment films being provided betweenthe seal material and the array substrate and between the seal materialand the counter substrate.

In this configuration, the grooves are provided in a seal region of apicture-frame region of the substrate in which the sealing material isprovided. Therefore, when an alignment film material is applied byinkjet printing, the grooves restrict the flow of the alignment filmmaterial to an outer part of the substrate. Thus, the alignment filmspreads to the midway portion of the seal region in the width directionthereof.

Here, the alignment films are each provided on a portion of a surface ofa corresponding one of the array substrate and the counter substratelocated from the midway portion of the sealing region in the widthdirection thereof toward the display region. Thus, the adhesivenessbetween each substrate and the sealing material is lower than in thecase where no alignment film is provided. In contrast, no alignment filmis provided from the midway portion of the sealing region in the widthdirection thereof in a direction away from the display region. Thus,each substrate is directly in contact with the sealing material, therebyobtaining excellent adhesiveness between each substrate and the sealingmaterial. Therefore, the array substrate is satisfactorily bonded to thecounter substrate with the sealing material, and a space in which aliquid crystal layer is provided is sufficiently enclosed.

A state of adhesion between a portion of the substrate and a portion ofthe sealing material that are located from the midway portion of thesealing region in the width direction thereof in a direction away fromthe display region is closely inspected. Part of the substrate in whichthe grooves have been formed is bonded to the sealing material withoutan organic insulating material or the like interposed between the partof the substrate and the sealing material. That is, part of the sealingmaterial corresponding to the part of the substrate in which the grooveshave been formed is bonded to a component made of an inorganic materialsuch as a transparent conductive film or metal, and the part of thesealing material and the substrate are firmly bonded together in thegrooves.

Thus, in the liquid crystal display device having the above-describedconfiguration, the plurality of grooves to restrict the flow of thealignment film material are formed in the seal region, so that the widthof the picture-frame region can be reduced without reducing theadhesiveness between each substrate and the sealing material.

At least part of an insulating film included in the array substrate ispreferably an organic insulating film, and the plurality of grooves arepreferably formed by removing portions of the organic insulating film.The plurality of grooves are more preferably formed by removing theportions of the organic insulating film extending across a thickness ofthe organic insulating film. In this case, the organic insulating filmis made of an acrylic resin.

With this configuration, at least the organic insulating film of thesecond insulating film is completely divided by the grooves into a partlocated inwardly from an inner edge of the seal region and a partlocated outwardly from an outer edge of the seal region. Therefore, evenwhen moisture or the like contained in external air enters the organicinsulating film from the side thereof remote from the display region,the moisture does not enter a portion of the second insulating filmtoward the display region. This reduces the risk that the adhesivenessat the interface between the alignment film and the second insulatingfilm deteriorates due to the moisture penetration. Thus, theadhesiveness between a portion of the sealing material and a portion ofeach substrate that are located from the midway portion of the sealingregion in the width direction thereof toward the display region can beincreased even in a region in which the alignment film is provided.

In the example liquid crystal display device of the present invention,the counter substrate may include a color filter layer at least in thedisplay region and a region provided with the sealing material, and thegrooves may be formed in positions which are located in the regionprovided with the sealing material and from which portions of the colorfilter layer are removed by a partial or total thickness of the colorfilter layer.

The counter substrate may include an overcoat layer at least in thedisplay region and a region provided with the sealing material, and thegrooves may be formed in positions which are located in the regionprovided with the sealing material and from which portions of theovercoat layer are removed by a partial or total thickness of theovercoat layer.

In the example liquid crystal display device of the present invention,in a region of the array substrate in which a first interconnect, afirst insulating film, a second interconnect, and a second insulatingfilm are sequentially stacked and the grooves overlap the firstinterconnect when viewed in plan, a stopper layer formed in a layeridentical with the second interconnect is preferably provided betweenthe first insulating film and the second insulating film.

With this configuration, each of the first interconnects is not exposedat the surfaces of the grooves in forming the grooves, so that the riskthat a leak occurs between adjacent ones of the first interconnects by asubstance such as conductive dust on surfaces of the grooves does notarise. Therefore, even when the grooves cross over the firstinterconnect, short circuits or the like between the adjacent ones ofthe first interconnects can be reduced.

In this case, a transparent conductive film is preferably provided onsurfaces of the grooves to cover at least the stopper layer.

With this configuration, the stopper layer is not exposed at thesurfaces of the grooves, so that deterioration of the stopper layer dueto corrosion can be reduced.

In the example liquid crystal display device of the present invention,the grooves including preferably two to twenty grooves are arranged inparallel.

Advantages of the Invention

According to the present invention, the width of a picture frame of aliquid crystal display device can be reduced without reducing theadhesiveness of a sealing material of a display panel of the liquidcrystal display device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view illustrating a liquid crystal display deviceaccording to a first embodiment.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1.

FIG. 3 is a plan view schematically illustrating an array substrateaccording to the first embodiment.

FIG. 4 is an enlarged plan view illustrating the region AR1 of FIG. 3.

FIG. 5 is an enlarged plan view illustrating the region AR2 of FIG. 4.

FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 5.

FIG. 7 is a cross-sectional view taken along the line VII-VII of FIG. 5.

FIG. 8 is a cross-sectional view illustrating a liquid crystal displaydevice according to a second embodiment.

FIG. 9 is a plan view schematically illustrating an array substrateaccording to a first variation.

FIG. 10 is a cross-sectional view illustrating a liquid crystal displaydevice according to the first variation.

FIG. 11 is a cross-sectional view illustrating a liquid crystal displaydevice according to a second variation.

FIG. 12 is a plan view schematically illustrating an array substrateaccording to a third variation.

FIG. 13 is a plan view schematically illustrating an array substrateaccording to a fourth variation.

FIG. 14 is a plan view schematically illustrating an array substrateaccording to a fifth variation.

FIG. 15 is a plan view schematically illustrating an array substrateaccording to a third embodiment.

FIG. 16 is a cross-sectional view illustrating a liquid crystal displaydevice according to the third embodiment.

FIG. 17 is a cross-sectional view illustrating a liquid crystal displaydevice according to a sixth variation.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described in detail belowbased on the drawings.

First Embodiment

(Liquid Crystal Display Device)

FIGS. 1 and 2 are views schematically illustrating an entire liquidcrystal display device 10 according to the present embodiment. FIG. 3 isa plan view schematically illustrating an array substrate 20. FIG. 4 isan enlarged view illustrating a region AR1 of FIG. 3. FIG. 5 is anenlarged view illustrating a region AR2 of FIG. 4. FIG. 6 is across-sectional view illustrating the liquid crystal display device,inclusive of a cross section taken along the line VI-VI of FIG. 5. FIG.7 is a cross-sectional view illustrating the liquid crystal displaydevice, inclusive of a cross section taken along the line VII-VII ofFIG. 5.

As illustrated in FIGS. 1 and 2, for the liquid crystal display device10, a frame-like picture-frame region F is defined in a substrateperipheral section, and a region surrounded by the picture-frame regionF is a display region D. The liquid crystal display device 10 includesthe array substrate 20 and a counter substrate 30 which face each other.The array substrate 20 and the counter substrate 30 are bonded to eachother at an outer peripheral part with an annular sealing material 40disposed as a frame-like seal region SL. A liquid crystal layer 50 isprovided in a space surrounded by the sealing material 40 between thesubstrates 20 and 30, thereby forming the display region D. Part of thearray substrate 20 in the picture-frame region F around the displayregion D protrudes beyond the counter substrate 30 and serves as aterminal region T to which an external connection terminal such as amount device will be mounted.

(Array Substrate)

When the array substrate 20 is provided with bottom-gate thin filmtransistors, the array substrate 20 is formed by stacking a firstconductive film (first interconnect) including gate signal lines (notshown), a gate insulating film 23 (first insulating film), a secondconductive film (second interconnect) including source signal lines (notshown), an interlayer insulating film 25 (second insulating film), and athird conductive film including pixel electrodes 26 a on a substratebody 21 (see FIG. 6). The first conductive film and the secondconductive film each include, for example, a titanium (Ti) film and acopper (Cu) film stacked on the Ti film. The gate insulating film 23(first insulating film) is, for example, a silicon nitride (SiNx) film.The interlayer insulating film 25 (second insulating film) includes, forexample, an inorganic insulating film (e.g., a silicon nitride (SiNx)film) as a passivation film and an organic insulating film (e.g., anacrylic resin film) stacked on the inorganic insulating film. When thethin film transistors are top gate transistors, the gate insulating film23 is formed before the first conductive film is formed, and aninsulating film covering the first conductive film is formed as thefirst insulating film.

Specifically, in the display region D of the array substrate 20, theplurality of gate signal lines are parallel to each other, the pluralityof source signal lines are parallel to each other, and the gate signallines are orthogonal to the source signal lines. A region surrounded byan adjacent pair of the gate signal lines and an adjacent pair of thesource signal lines forms a single pixel. Each thin film transistor isprovided for a corresponding one of the pixels. Each pixel electrode 26a corresponds to an associated one of the thin film transistors. Theinterlayer insulating film 25 covers the entire surface of thesubstrate, inclusive of the picture-frame region F. In the picture-frameregion F of the array substrate 20, the source signal lines and the gatesignal lines are lead out via lead lines (e.g., interconnects 22 a inFIGS. 6 and 7) to the terminal region T. The gate signal lines areconnected to gate drivers (not shown), and the source signal lines areconnected to source drivers (not shown).

On a surface of the array substrate 20 facing the liquid crystal layer50, an alignment film 27 is provided to cover an area including thedisplay region D. As illustrated in FIG. 5, the alignment film 27extends outwardly from the display region D to a midway portion of theseal region SL in a width direction thereof. The alignment film 27 ismade of, for example, a polyimide resin, etc.

As illustrated in FIGS. 3 and 4, a plurality of grooves 28 are providedin the seal region SL of the array substrate 20 to have an annular shapesurrounding the display region D. The grooves 28 are spaced apart fromeach other in a width direction of the sealing material 40 and extendalong the sealing material 40. Two to twenty grooves 28 are preferablyprovided (six grooves in FIGS. 3-7). As illustrated in FIGS. 6 and 7,the grooves 28 are provided at positions from which the interlayerinsulating film 25 has been removed. Each groove 28 has a width of 2-50μm, more preferably 4-20 μm. The grooves 28 are aligned at a pitch of,for example, 4-100 μm.

As illustrated in FIGS. 5 and 6, island-like stopper layers 24 a areprovided in regions which will be bottom surfaces of the grooves 28, andthe regions correspond to positions at which the grooves 28 cross overthe interconnects 22 a. The stopper layers 24 a are formed from thesecond conductive film at the same time as the source signal lines areformed. Since the stopper layers 24 a are provided, the interconnects 22a located at the bottom surfaces of the grooves 28 are not exposed insurfaces of the grooves 28. This also eliminates or reduces the riskthat a leak is caused between the adjacent interconnects 22 a by asubstance such as conducive dust on the surfaces of the grooves 28.Therefore, even when the grooves 28 cross over the interconnects 22 a orthe like made from the first conductive film, problems such as a shortcircuit between the interconnects 22 a do not arise.

Some of the stopper layers 24 a may be connected to a transfer pad (notshown) configured to apply a common electric potential to a commonelectrode 34 which will be described later. In this case, while thestopper layers 24 a may be electrically continuous with the commonelectrode 34 via, for example, conductive beads (not shown), the stopperlayers 24 a and the common electrode 34 are then simply kept at thecommon electric potential, and problems such as a display defect causedby the leak of a current do not arise.

The other stopper layers 24 a which are not connected to the transferpad are in a floating state. Even when the stopper layers 24 a in thefloating state are electrically continuous with the common electrode 34,problems such as a display defect caused by the leak of a current do notarise.

At the positions at which the grooves 28 cross over the interconnects 22a, island-like transparent conductive films 26 b are further provided sothat the surfaces of the grooves 28 are covered with the transparentconductive film 26 b. With this configuration, the stopper layers 24 aprovided at the bottom surfaces of the grooves 28 are not exposed at thesurfaces of the grooves 28, so that deterioration of the stopper layers24 a due to corrosion is reduced. The transparent conductive films 26 bare formed from the third conductive film at the same time as the pixelelectrodes 26 a are formed. The transparent conductive films 26 b arenot essential elements.

(Counter Substrate)

The counter substrate 30 includes color filter layers 32 a, a blackmatrix 33, and the common electrode 34 which are stacked on a substratebody 31. In the picture-frame region F in the outer peripheral part ofthe substrate, the black matrix 33 forms a light-shielding region (notshown). Specifically, in the display region D of the counter substrate30, each of the color filter layers 32 a corresponds to an associatedone of the pixels and is colored with, for example, red, green, or bluedepending on the display color. The black matrix 33 is provided in thelight-shielding region defining the color filter layers 32 a. The commonelectrode 34 covers the entire surface of the substrate, inclusive ofthe picture-frame region F. The common electrode 34 is kept at a commonelectric potential via, for example, a conductive bead (not shown) mixedin the sealing material 40. The common electric potential is applied viaa transfer pad (not shown) provided in the picture-frame region F of thearray substrate 20. In the picture-frame region F of the countersubstrate 30, color filter layers 32 b are made of a resin which is thesame as a material forming the color filter layers 32 a. The colorfilter layers 32 b correspond to at least the seal region SL of thepicture-frame region F.

On a surface of the counter substrate 30 facing the liquid crystal layer50, an alignment film 35 is provided to cover an area including thedisplay region D. The alignment film 35 extends outwardly from thedisplay region D to the midway portion of the seal region SL in thewidth direction thereof. The alignment film 35 is made of, for example,a polyimide resin, etc.

Similarly to the array substrate 20, a plurality of annular grooves 36are provided in the seal region SL of the counter substrate 30 tosurround the display region D (see FIGS. 6 and 7). The grooves 36 arespaced apart from each other in the width direction of the sealingmaterial 40 and extend along the sealing material 40. Two to twentygrooves 36 are preferably provided (six grooves in FIG. 6). Asillustrated in FIGS. 6 and 7, the grooves 36 are provided at positionsfrom which the color filter layers 32 b formed in a layer identical withthe color filter layers 32 a have been removed. Each groove 36 has awidth of 2-50 μm, more preferably 4-20 μm. The grooves 36 are aligned ata pitch of, for example, 4-100 μm.

The array substrate 20 has the annular grooves 28 surrounding thedisplay region D, and the counter substrate 30 has the annular grooves36 surrounding the display region D. This reduces the flow of a liquidmaterial of the alignment film from the display region D toward thepicture-frame region F in forming the alignment films 27, 35. Thus, thearea where the alignment film material spreads out can be reduced.

As described above, the sealing material 40 is provided in an annularform outside the display region D and bonds the array substrate 20 tothe counter substrate 30. As illustrated in FIGS. 6 and 7, surfaces ofsome of the grooves 28 (four of the six grooves 28 in FIGS. 6 and 7) arecovered with the alignment film 27, and surfaces of some of the grooves36 (four of the six grooves 36 in FIGS. 6 and 7) are covered with thealignment film 35. Part of the sealing material 40 located from themidway portion in the width direction toward the display region D fillsthe grooves 28, 36 having surfaces respectively covered with thealignment films 27, 35 and is in contact with the alignment films 27,35. On the other hand, part of the sealing material 40 located from themidway portion in the width direction in a direction away from thedisplay region D (a direction opposite to the display region) isdirectly in contact with the interlayer insulating film 25 and thetransparent conductive film 26 b of the array substrate 20, and isdirectly in contact with the common electrode 34 of the countersubstrate 30 because no alignment films 27, 35 are provided.

Glass fiber ground products 41 serving as spacers to keep a uniformdistance between the array substrate 20 and the counter substrate 30 aremixed in the sealing material 40. The glass fiber ground products 41have, for example, a fiber diameter of about 4-8 μm and a length ofabout 10-100 μm. The glass fiber ground products 41 whose fiber diameterand length are larger than the widths of the grooves 28 and 36 arepreferably used, so that the glass fiber ground products 41 do not fallin the grooves 28 or the grooves 36. When the fibers cannot have alarger diameter than the widths of the grooves, it is sufficient if thelength of the fibers is larger than the widths of the grooves. The glassfiber ground products 41 are sandwiched between a surface of theinterlayer insulating film 25 and a surface of the color filter layers32 b, thereby keeping the distance between the array substrate 20 andthe counter substrate 30 uniform.

The liquid crystal layer 50 is made of, for example, nematic liquidcrystals.

When a TFT in each pixel of the liquid crystal display device 10 havingthe above-described configuration is turned on, a potential differenceoccurs between the pixel electrode 26 a and the common electrode 34, sothat a predetermined voltage is applied to a liquid crystal capacitormade of the liquid crystal layer 50. The alignment of liquid crystalmolecules of the liquid crystal display device 10 varies depending onthe applied voltage. The liquid crystal display device 10 uses thevariation in the alignment to adjust the transmittance of incident lightfrom outside, thereby displaying a desired image.

(Method for Fabricating Liquid Crystal Display Device)

Next, a method for fabricating a liquid crystal display device havingthe above-described configuration will be described.

First, a first conductive film including gate signal lines andinterconnects 22 a, a gate insulating film 23, and a second conductivefilm including source signal lines and stopper layers 24 a aresequentially stacked on a substrate body 21 by using a known method.

Next, for example, a silicon nitride (SiNx) film is formed as aninorganic insulating film to cover the entire surface of the substrate,and an acrylic resin film is further formed as an organic insulatingfilm, thereby forming an interlayer insulating film 25. Then, theacrylic resin film as the organic insulating film, which isphotosensitive, is exposed to light and is then developed to removeportions of the acrylic resin film corresponding to grooves 28. Further,the silicon nitride (SiNx) film is dry etched using the acrylic resinfilm as a mask, thereby removing portions of the silicon nitride filmcorresponding to the grooves 28. In this way, the grooves 28 are formed.Alternatively, when the organic insulating film is made of anon-photosensitive acrylic resin, a resist is applied to the organicinsulating film and is then developed, and the organic and inorganicinsulating films are further etched separately or at the same time toremove portions of the interlayer insulating film 25, thereby formingthe grooves 28. At this time, the stopper layers 24 a or the substratebody 21 is fully exposed at surfaces of the grooves 28 formed byremoving the portions of the interlayer insulating film 25.

Next, a third conductive film including pixel electrodes 26 a andtransparent conductive films 26 b and made of a transparent conductivematerial such as ITO or IZO is stacked.

Moreover, an alignment film 27 is formed by inkjet printing to cover thedisplay region D. At this time, liquid polyimide which is an alignmentfilm material flows to and spreads over the picture-frame region F.However, the grooves 28 restrict the spread of the polyimide. Therefore,no polyimide film is formed in some of the grooves 28 in positionslocated outwardly from the midway portion of the seal region SL

On the other hand, color filter layers 32 a, 32 b and a black matrix 33are formed on a substrate body 31 by a known method and are developedafter exposure of the color filter layer 32 b to light to removeportions of the color filter layer 32 b, thereby forming the grooves 36.When the color filter layer 32 b is not photosensitive, a resist isapplied to the color filter layer 32 b and is then developed. The colorfilter layer 32 b is further etched to remove portions thereof, therebyforming the grooves 36. A common electrode 34 is stacked to cover thecolor filter layers 32 a, 32 b and the black matrix 33. In a mannersimilar to the alignment film 27 of the array substrate 20, an alignmentfilm 35 is stacked. At this time, liquid polyimide which is an alignmentfilm material flows to and spreads over the picture-frame region F.However, the grooves 36 restrict the spread of the polyimide. Therefore,no polyimide film is formed in some of the grooves 36 located outwardlyfrom the midway portion of the seal region SL.

Subsequently, a sealing material 40 is applied to a surface of thefabricated array substrate 20 or the fabricated counter substrate 30,and a liquid crystal material is dropped on a region surrounded by thesealing material 40. Then, the two substrates are placed one overanother, and the sealing material 40 is hardened, thereby bonding thesubstrates 20, 30 to each other. Thus, a display panel is fabricated.

In addition to the above-described processes, a vacuum injection processusing a capillary phenomenon may be performed to inject the liquidcrystal material into a space between the two substrates 20, 30. In thiscase, specifically, the sealing material 40 is applied in a frame-likeshape having an opening which will be an inlet of the liquid crystalmaterial. Then, the substrates 20, 30 are bonded to each other, and thesealing material 40 is hardened. The substrates are divided into cells,and then the liquid crystal material is injected through the opening inthe sealing material 40 under a vacuum environment. Finally, the inletis sealed with an end-sealing material.

Finally, the substrates are divided into cells. Then, a polarizer isstuck to the liquid crystal display panel, parts are mounted, andmodularization processes, etc. (e.g., assembly of the backlight) areperformed. In this way, the liquid crystal display device 10 isfabricated.

Advantages of First Embodiment

In the liquid crystal display device 10 having the configuration of thepresent embodiment, the grooves 28 and the grooves 36 are respectivelyprovided in the array substrate 20 and the counter substrate 30 in theseal region SL of the picture-frame region F. Therefore, when analignment film material is applied by inkjet printing, the groovesrestrict the spread of the alignment film material to the outer portionof the substrates, so that the alignment films 27, 35 spread to themidway portion of the seal region SL in the width direction thereof (seethe hatched region in FIG. 5).

Here, the alignment films 27 and 35 are provided on a portion of thesurface of a corresponding one of the array substrate 20 and the countersubstrate 30 located inwardly from the midway portion of the seal regionSL in the width direction. Therefore, the adhesiveness between thesubstrates and the sealing material 40 is lower than in the case whereno alignment film is provided. However, no alignment films 27, 35 areformed outwardly from the midway portion of the seal region SL in thewidth direction. Therefore, excellent adhesiveness can be obtainedbetween each of the substrates and the sealing material 40. Therefore,the array substrate 20 and the counter substrate 30 are satisfactorilybonded to each other with the sealing material 40, and the space inwhich the liquid crystal layer 50 is provided is sufficiently enclosedwith the sealing material 40.

The adhesion of a portion of the array substrate 20 and a portion of thesealing material 40 that are located outwardly from the midway portionof the seal region SL in the width direction thereof is inspected. Inthis case, in part of the array substrate 20 in which the grooves 28have been formed, the transparent conductive films 26 b (see FIG. 6) orthe substrate body 21 (see FIG. 7) is bonded to the sealing material 40.That is, regions of the sealing material 40 corresponding to the grooves28 are bonded to an element made of an inorganic material and are firmlybonded to the array substrate 20.

The adhesion of a portion of the counter substrate 30 and a portion ofthe sealing material 40 that are located outwardly from the midwayportion of the seal region SL in the width direction thereof isinspected. In this case, in parts of the counter substrate 30 in whichthe grooves 36 have been formed, the common electrode 34 (see FIG. 6) isbonded to the sealing material 40. That is, regions of the sealingmaterial 40 corresponding to the grooves 36 are bonded to an elementmade of an inorganic material and are firmly bonded to the countersubstrate 30.

In the liquid crystal display device 10 of the present embodiment, theplurality of grooves 28, 36 to restrict the spread of the alignment filmmaterial are provided in the seal region SL. Thus, the width of thepicture-frame region F can be reduced without reducing the adhesivenessto the substrates.

In the liquid crystal display device 10 of the present embodiment, thestopper layers 24 a are provided at the bottom surfaces of the grooves28 in the array substrate 20. Therefore, the interlayer insulating film25 made of an organic insulating material is completely removed from thebottom surfaces of the grooves 28. That is, part of the interlayerinsulating film 25 located outwardly from the seal region SL iscompletely separated from part of the interlayer insulating film 25located inwardly from the seal region SL by the annular grooves 28.Therefore, even in the case of entrance of moisture or the like into thepart of the interlayer insulating film 25 located outwardly from theseal region SL and exposed to external air, the moisture does notpermeate the part of the interlayer insulating film 25 located inwardlyfrom the seal region SL. This eliminates or reduces the risk that thepermeation of the moisture reduces the adhesiveness at the interfacebetween the alignment film and the interlayer insulating film 25.

Second Embodiment

Next, a liquid crystal display device 10 of a second embodiment will bedescribed. In the present embodiment, configurations identical with orcorresponding to the configurations of the first embodiment are labeledwith the same reference characters as shown in the first embodiment fordescription.

Similarly to the first embodiment, the liquid crystal display device 10includes an array substrate 20 and a counter substrate 30 which faceeach other and are bonded to each other with a sealing material 40disposed at their outer peripheral parts, wherein a liquid crystal layer50 is provided as a display layer in a space surrounded by the sealingmaterial 40. Unlike the first embodiment, the liquid crystal displaydevice 10 of the second embodiment is configured as an in planeswitching (IPS) liquid crystal display. That is, the second embodimentis different from the first embodiment in that a common electrode isprovided on the array substrate 20, but not on the counter substrate 30,and that pixel electrodes 26 a are provided in a comb teeth-pattern whenviewed in plan.

As illustrated in FIG. 8, the array substrate 20 includes a firstconductive film including gate signal lines (not shown), a gateinsulating film 23, a second conductive film including source signallines (not shown), a first interlayer insulating film 25 a, a firsttransparent electrode provided as a common electrode 29, a secondinterlayer insulating film 25 b, a second transparent electrodeincluding the pixel electrodes 26 a, and an alignment film 27 which arestacked on a substrate body 21. The first interlayer insulating film 25a is made of an inorganic insulating material such as silicon nitride(SiNx). The second interlayer insulating film 25 b is made of an organicinsulating material such as an acrylic resin.

Grooves 28 are provided in positions from which portions of the firstand second interlayer insulating films 25 a, 25 b have been removed.Similarly to the first embodiment, stopper layers 24 a under the firstinterlayer insulating film 25 a are exposed at bottoms of the grooves28. Transparent conductive films 26 b cover surfaces of the grooves 28,inclusive of the stopper layers 24 a. When the second interlayerinsulating film 25 b is made of a photosensitive acrylic resin, thephotosensitive acrylic resin is exposed to light, and then, the secondinterlayer insulating film 25 b is developed. The first interlayerinsulating film 25 a (silicon nitride film) is dry etched using theacrylic resin as a mask to remove portions of the first interlayerinsulating film 25 a, thereby forming the grooves 28. Alternatively,when the second interlayer insulating film 25 b is made of anon-photosensitive acrylic resin, a resist is applied to the secondinterlayer insulating film 25 b and is then developed, and the secondinterlayer insulating film 25 b is etched to remove portions of thesecond interlayer insulating film 25 b. A resist is further applied tothe first interlayer insulating film 25 a and is then developed, and thefirst interlayer insulating film 25 a is etched to remove portions ofthe first interlayer insulating film 25 a, thereby forming the grooves28. The first interlayer insulating film 25 a and the second insulatingfilm 25 b may be simultaneously developed and etched to form the grooves28. Alternatively, after the first interlayer insulating film 25 a(silicon nitride film) is formed and before the second interlayerinsulating film 25 b is formed, portions of the first interlayerinsulating film 25 a corresponding to the grooves 28 may be removed byetching, and the first transparent electrode including the commonelectrode 29 and the second interlayer insulating film 25 b(photosensitive acrylic resin) may be formed and developed to remove theportions of the second interlayer insulating film 25 b corresponding tothe grooves 28, thereby forming the grooves 28.

The counter substrate 30 includes color filter layers 32 a, a blackmatrix 33, an overcoat layer 37, and an alignment film 35 which arestacked on a substrate body 31. Specifically, the overcoat layer 37 ismade of, for example, a transparent acrylic resin and is provided on theentire surface of the substrate to cover the color filter layers 32 aand the black matrix 33.

Grooves 36 are provided in regions from which portions of the overcoatlayer 37 provided in the picture-frame region F have been removed. Thegrooves 36 are formed by developing the overcoat layer 37 after exposureof the overcoat layer 37 to light. Alternatively, when the overcoatlayer 37 is non-photosensitive, the grooves 36 are formed in a mannersuch that a resist is applied to the overcoat layer 37 and is thendeveloped, and the overcoat layer 37 is further etched to remove theportions of the overcoat layer 37.

Other configurations are based on the configuration of a display similarto that of the first embodiment or a generally known IPS liquid crystaldisplay.

In the liquid crystal display device 10 having the above-describedconfiguration, a predetermined voltage is applied on a pixel-by-pixelbasis to the liquid crystal layer 50 between each of the pixelelectrodes 26 a on the array substrate 20 and the common electrode 29 toinduce an electric field in a lateral direction, thereby varying thealignment of the liquid crystal layer 50. In this way, the transmittanceof light transmitted through the display panel is adjusted, so that adesired image is displayed.

The liquid crystal display device 10 having the above-describedconfiguration can be fabricated by the fabrication method of the firstembodiment based on a production method of a conventional IPS liquidcrystal display device.

The liquid crystal display device 10 having the above-describedconfiguration includes no common electrode on the counter substrate 30,so that a surface of the substrate body 31 is exposed in a region inwhich the alignment film 35 is not provided. Therefore, a sealingmaterial 40 is directly bonded to the substrate body 31, which is aglass substrate. Thus, an increased adhesiveness can be obtained betweenthe counter substrate 30 and the sealing material 40.

Other configurations and advantages are similar to those described inthe first embodiment.

(First Variation)

In the above-described embodiments, it has been described that in thearray substrate 20 and the counter substrate 30, all of the plurality ofgrooves 28, 36 are provided in the seal region SL. However, theembodiments are not limited to this configuration. For example, as shownin a first variation illustrated in FIGS. 9 and 10, the inner two of sixgrooves 28 may be provided inwardly from the seal region SL. Also inthis case, four of the grooves 28 for restricting the outward spread ofthe alignment film material are provided in the seal region SL. Thus,the width of the picture-frame region F can be reduced.

(Second Variation)

In the above-described embodiments, it has been described that sixgrooves are provided in each of the array substrate 20 and the countersubstrate 30. However, the number of grooves may be different betweenthe two substrates. For example, as shown in a second variationillustrated in FIG. 11, six grooves 28 may be provided in the arraysubstrate 20, whereas seven grooves 36 may be provided in the countersubstrate 30. In this case, positions of the grooves 28 in the arraysubstrate 20 do not correspond on a one-to-one basis to positions of thegrooves 38 in the counter substrate 30. However, glass fiber groundproducts 41 mixed as spacers in the sealing material 40 are sandwichedbetween the array substrate 20 and the counter substrate 30, so that noproblem arises.

(Third Variation)

In the above-descried embodiments, it has been described that in thearray substrate 20 and the counter substrate 30, the grooves 28, 36 areprovided in a frame-like shape along the seal region SL. However, theembodiments are not limited to this configuration. For example, thegrooves may extend along only one side of the seal region SL. Forexample, as shown in a third variation illustrated in FIG. 12, when aterminal region T is defined along one side (upper side in FIG. 12) ofthe array substrate 20, grooves 28 may be provided along the upper side.

(Fourth Variation)

The grooves 28, 36 may be, but not limited to, such a continuouslyextending configuration as described in the above-described embodiments.For example, as shown in a fourth variation illustrated in FIG. 13, thegrooves 28 may be discontinuously formed in a broken line pattern. Inthis case, the grooves 28 are formed in a staggered pattern so thatadjacent grooves 28 are not adjacent to a region in which no groove isformed. This can enhance the effect of reducing the spread of thealignment film material.

In addition to the above-described embodiment, a silicon layer made ofthe same material as the semiconductor layer of the thin film transistormay be provided in an island pattern between the gate insulating film 23and each stopper layer 24 a. Even when raised portions are formed on asurface of the gate insulating film 23 due to the interconnects 22 a,providing a silicon layer under the stopper layer 24 a can furtherensure prevention of a leak.

(Fifth Variation)

In the above-described embodiments, it has been described that informing the grooves 28 in the array substrate 20, the portions of bothof the organic insulating film and the inorganic insulating film of theinterlayer insulating film 25 are removed to expose the stopper layers24 a or the substrate body 21 at the surfaces of the grooves 28.However, it is sufficient when the portions of at least the organicinsulating film of the interlayer insulating film 25 are removed. Forexample, in the case of the IPS liquid crystal display device 10 inwhich the first interlayer insulating film 25 a is made of an inorganicinsulating material such as silicon nitride (SiNx) and the secondinterlayer insulating film 25 b is made of an organic insulatingmaterial such as an acrylic resin as in the second embodiment, it ispossible to form the grooves 28 only in the second interlayer insulatingfilm 25 b by using the first interlayer insulating film 25 a as astopper layer in forming the grooves 28 as shown in a fifth variationillustrated in FIG. 14. In this case, the first interlayer insulatingfilm 25 a is used as a stopper layer, so that it is not necessary toform the stopper layers 24 a from the second conductive film.

(Other Variations)

In the above-described embodiments, it has been described that the blackmatrix 33 is provided at the interface between the display region D andthe picture-frame region F of the counter substrate 30 so that theinterface is shielded against light. However, the interface between thedisplay region D and the picture-frame region F may be shielded againstlight at the array substrate 20 but not at the counter substrate 30. Inthis case, for example, the interface can be shielded against light byusing the second conductive film.

In the above-described embodiments, it has been described that thegrooves 28 and 36 are respectively formed in the array substrate 20 andthe counter substrate 30. However, the grooves 28 may be formed in thearray substrate 20, whereas no groove may be formed in the countersubstrate 30. In this case, a predetermined region of the countersubstrate 30 on which a transfer pad, and the like are provided can beirradiated with a laser, or the like to partially remove the alignmentfilm 35, so that the picture-frame region of the counter substrate 30has a reduced width substantially equal to the width of thepicture-frame region of the array substrate 20.

Third Embodiment

Next, a liquid crystal display device 10 of a third embodiment will bedescribed. In the present embodiment, configurations identical with orcorresponding to the configurations of the first and second embodimentare labeled with the same reference characters as shown in the first andsecond embodiments for description.

Similarly to the first embodiment, the liquid crystal display device 10includes an array substrate 20 and a counter substrate 30 which faceeach other and are bonded to each other with a sealing material 40provided at their outer peripheral parts, wherein a liquid crystal layer50 is provided as a display layer in a space surrounded by the sealingmaterial 40.

As illustrated in FIG. 15, the liquid crystal display device 10 isdifferent from that of each of the first and second embodiments in thata gate driver region GD and a source driver region SD are arrangedinwardly from a seal region SL. The liquid crystal display device 10 isa fringe field switching (FFS) liquid crystal display including TFTshaving a top gate structure. That is, similarly to the secondembodiment, a common electrode 29 is formed on the array substrate 20,but not on the counter substrate 30, to have a slit, and pixelelectrodes 26 a are each provided on the entire surface of acorresponding one of the pixels when viewed in plan.

As illustrated in FIG. 16, the array substrate 20 includes a firstinorganic insulating film 21B, a semiconductor film 21C, a gateinsulating film 23, a first conductive film including gate electrodes22, a second inorganic insulating film 23B, a second conductive filmincluding interconnect layers 24 a and source/drain electrodes 24 b, anorganic insulating film 25 a, a first transparent conductive filmincluding the pixel electrodes 26 a, a third inorganic insulating film25 b, a second transparent conductive film provided as a commonelectrode 29, and an alignment film 27 which are stacked on a substratebody 21. The first inorganic insulating film 21B, the second inorganicinsulating film 23B, and the third inorganic insulating film 25 b aremade of, for example, an inorganic insulating material such as a siliconoxide film (SiO₂) or silicon nitride (SiNx). The organic insulating film25 a is made of, for example, an organic insulating material such as anacrylic resin. The semiconductor film 21C, the gate electrode 22, andthe source/drain electrodes 24 b form the TFT having a top gatestructure. For example, a low temperature polysilicon (LTPS) film or acontinuous grain silicon (CG silicon) film is used as the semiconductorfilm 21C.

Grooves 28 are provided in positions from which the organic insulatingfilm 25 a has been removed. The third inorganic insulating film 25 bcovers surfaces of the grooves 28. Some of the grooves 28 located in aregion overlapping gate metal 22 b and a semiconductor film 21 Cb may beprovided with the interconnect layers 24 a as stopper layers made of thesame second conductive film as the source/drain electrodes 24 b ifnecessary. Here, the semiconductor film 21Cb and the gate metal 22 b,which the grooves 28 overlap, form part of the gate driver GD. When theorganic insulating film 25 a is made of a photosensitive acrylic resin,the photosensitive acrylic resin is exposed to light, and then, theorganic insulating film 25 a is developed, thereby forming the grooves28. Alternatively, when the organic insulating film 25 a is made of anon-photosensitive acrylic resin, a resist is applied to the organicinsulating film 25 a and is then developed, and the organic insulatingfilm 25 a is etched to remove portions of the organic insulating film 25a. A resist is further applied to the organic insulating film 25 a andis then developed, and the organic insulating film 25 a is etched toremove portions of the organic insulating film 25 a, thereby forming thegrooves 28. In this case, the second conductive film may be provided asa stopper layer in groove regions so that the insulating film under theorganic insulating film is not removed by etching.

The interconnect layers 24 a are used as interconnects. Therefore, theinterconnect layers 24 a may also be provided in regions in which thesemiconductor film 21Cb and the gate metal 22 b forming part of the gatedriver GD are not provided. The surfaces of the grooves 28 may becovered with a first transparent conductive film identical with thepixel electrodes 26 a or a second transparent conductive film identicalwith the common electrode 29. When the surfaces of the grooves 28 arecovered with the first transparent conductive film or the secondtransparent conductive film, and the underlying interconnect layers 24a, or the like are used as interconnects, a design in which a shortcircuit via the transparent conductive films is not formed between theinterconnects is required. For example, a patterning design in which theinterconnect layers 24 a and the transparent conductive film do notoverlap each other or a design in which a second inorganic insulatingfilm 25 b, or the like is provided between the interconnect layers 24 aand the transparent conductive film is required.

The counter substrate 30 includes a color filter layers 32 a, a blackmatrix 33, an overcoat layer 37, and an alignment film 35 which arestacked on a substrate body 31. Specifically, the overcoat layer 37 ismade of, for example, a transparent acrylic resin and is provided on theentire surface of the substrate to cover the color filter layers 32 aand the black matrix 33.

Grooves 36 are provided in positions from which the overcoat layer 37 inthe picture-frame region F has been removed. The grooves 36 are formedby developing the overcoat layer 37 after exposure of the overcoat layer37 to light. Alternatively, when the overcoat layer 37 isnon-photosensitive, a resist is applied to the overcoat layer 37 and isthen developed, and the overcoat layer 37 is further etched to removeportions of the overcoat layer 37.

Other configurations are based on the configuration of a display similarto that of the first embodiment or a generally known IPS liquid crystaldisplay.

In the liquid crystal display device 10 having the above-describedconfiguration, a predetermined voltage is applied on a pixel-by-pixelbasis to the liquid crystal layer 50 between each of the pixelelectrodes 26 a and the common electrode 29 on the array substrate 20 toinduce a fringing electric field in a lateral direction, thereby varyingthe alignment of the liquid crystal layer 50. In this way, thetransmittance of light transmitted through the display panel isadjusted, so that a desired image is displayed.

The liquid crystal display device 10 having the above-describedconfiguration can be fabricated by the fabrication method of the firstembodiment based on a production method of a conventional IPS liquidcrystal display device.

In the liquid crystal display device 10 having the above-describedconfiguration, the source driver region SD and the gate driver region GDare located inwardly from the seal region SL. Thus, circuits provided inthe source driver region SD and the gate driver region GD can be in anenclosed space between the array substrate 20 and the counter substrate30. In the seal region SL, the grooves 28 divide the organic insulatingfilm into an inner portion and an outer portion. This reduces moisture,oxygen, or the like outside the enclosed space entering the enclosedspace through the organic insulating film. Thus, the circuits in thepixel region as well as the circuits provided in the source driverregion SD and the gate driver region GD can be less susceptible tomoisture- or oxygen-caused deterioration.

The liquid crystal display device 10 having the above-describedconfiguration includes no common electrode on the counter substrate 30,so that a surface of the substrate body 31 is exposed in a region inwhich the alignment film 35 is not provided. Therefore, a sealingmaterial 40 is directly bonded to the substrate body 31, which is aglass substrate. Thus, an increased adhesiveness can be obtained betweenthe counter substrate 30 and the sealing material 40.

Other configurations and advantages are similar to those described inthe first embodiment.

(Sixth Variation)

In the third embodiment, it has been described that the FFS liquidcrystal display as the liquid crystal display device 10 includes TFTshaving a top gate structure. However, as shown in a sixth variationillustrated in FIG. 17, an FFS liquid crystal display may include TFTshaving a bottom gate structure.

In this case, as illustrated in FIG. 17, an array substrate 20 includesa first conductive film containing gate electrodes 22, a gate insulatingfilm 23, a semiconductor film 21C, a second conductive film includinginterconnect layers 24 a and source/drain electrodes 24 b, a firstinorganic insulating film 23B, an organic insulating film 25 a, a firsttransparent conductive film provided as a common electrode 29, a secondinorganic insulating film 25 b, a second transparent conductive filmincluding pixel electrodes 26 a, and an alignment film 27 which arestacked on a substrate body 21. The first inorganic insulating film 23Band second inorganic insulating film 25 b are made of, for example, aninorganic insulating material such as silicon nitride (SiNx). Theorganic insulating film 25 a is made of, for example, an organicinsulating material such as an acrylic resin. The gate electrode 22, thesemiconductor film 21C, and the source/drain electrodes 24 b form a TFThaving a bottom gate structure. For example, an amorphous silicon (a-Si)film, an oxide semiconductor film (e.g., an In—Ga—Zn-based oxide(In—Ga—Zn—O) film), or the like is used as the semiconductor film 21C.As illustrated in FIG. 17, the TFT includes TFTs for pixel drive andTFTs in circuits in the gate driver region GD. The TFTs in the circuitsin the gate driver region GD may overlap the grooves 28 as illustratedin FIG. 17 or may be provided not to overlap the grooves 28.

The grooves 28 are provided in positions from which the organicinsulating film 25 a has been removed. A second inorganic insulatingfilm 25 b covers surfaces of the grooves 28. When the organic insulatingfilm 25 a is made of a photosensitive acrylic resin, the photosensitiveacrylic resin is exposed to light, and then, the organic insulating film25 a is developed, thereby forming the grooves 28. Alternatively, whenthe organic insulating film 25 a is made of a non-photosensitive acrylicresin, a resist is applied to the organic insulating film 25 a and isthen developed, and the organic insulating film 25 a is etched to removeportions of the organic insulating film 25 a. A resist is furtherapplied to the organic insulating film 25 a and is then developed, andthe organic insulating film 25 a is etched to remove the portions of theorganic insulating film 25 a, thereby forming the grooves 28.

The counter substrate 30 and other configurations are similar to thosein the third embodiment.

In the liquid crystal display device 10 having the above-describedconfiguration, a predetermined voltage is applied on a pixel-by-pixelbasis to the liquid crystal layer 50 between each of the pixelelectrodes 26 a and the common electrode 29 on the array substrate 20 toinduce a fringing electric field in a lateral direction, thereby varyingthe alignment of the liquid crystal layer 50. In this way, thetransmittance of light transmitted through the display panel isadjusted, so that a desired image is displayed.

INDUSTRIAL APPLICABILITY

The present invention is useful for liquid crystal display devices. Thepresent invention is useful, in particular, for a structure to control aregion of a picture-frame region of a display panel to which analignment film is applied.

DESCRIPTION OF REFERENCE CHARACTERS

-   10 Liquid Crystal Display Device-   20 Array Substrate-   21 Substrate Body-   22 a Interconnect (First Interconnect)-   23 Gate Insulating Film (First Insulating Film)-   24 a Stopper Layer (Second Interconnect)-   25 Interlayer Insulating Film (Second Insulating Film)-   26 b Transparent Conductive Film-   27 Alignment Film-   28 Groove-   30 Counter Substrate-   32 a Color Filter Layer-   32 b Color Filter Layer-   34 Common Electrode-   35 Alignment Film-   36 Groove-   37 Overcoat Layer-   40 Sealing Material-   50 Liquid Crystal Layer

1. A liquid crystal display device comprising: an array substrate; acounter substrate facing the array substrate; a sealing material whichis provided outside a display region and by which the array substrate isbonded to the counter substrate; a liquid crystal layer in a regionsurrounded by the sealing material between the array substrate and thecounter substrate; and alignment films each provided on a surface of acorresponding one of the array substrate and the counter substratefacing the liquid crystal layer to cover an area including the displayregion, wherein a plurality of grooves are provided in the surface ofthe array substrate facing the liquid crystal layer to extend along thesealing material, and are spaced apart from each other in a widthdirection of the sealing material, each alignment film covers surfacesof some or all of the grooves located from a midway portion of thesealing material in a width direction thereof toward the display region,and is in contact with the sealing material, and part of the sealingmaterial located from the midway portion in the width direction in adirection away from the display region is directly in contact with thearray substrate without the alignment film being provided between theseal material and the array substrate.
 2. The liquid crystal display ofclaim 1, wherein a plurality of grooves are provided in the surface ofthe counter substrate facing the liquid crystal layer to extend alongthe sealing material, and are spaced apart from each other in a widthdirection of the sealing material, each alignment film covers surfacesof some or all of the grooves in the array substrate and the countersubstrate located from the midway portion of the sealing material in thewidth direction thereof toward the display region, and is in contactwith the sealing material, and the part of the sealing material locatedfrom the midway portion in the width direction in a direction away fromthe display region is directly in contact with the array substrate andthe counter substrate without the alignment films being provided betweenthe seal material and the array substrate and between the seal materialand the counter substrate.
 3. The liquid crystal display device of claim1 or 2, wherein at least part of an insulating film included in thearray substrate is an organic insulating film, and the plurality ofgrooves are formed by removing portions of the organic insulating film.4. The liquid crystal display device of claim 3, wherein the pluralityof grooves are formed by removing the portions of the organic insulatingfilm extending across a thickness of the organic insulating film.
 5. Theliquid crystal display device of claim 3, wherein the organic insulatingfilm is made of an acrylic resin.
 6. The liquid crystal display deviceof claim 2, wherein the counter substrate includes a color filter layerat least in the display region and a region provided with the sealingmaterial, and the grooves are formed in positions which are located inthe region provided with the sealing material and from which portions ofthe color filter layer are removed by a partial or total thickness ofthe color filter layer.
 7. The liquid crystal display device of claim 2,wherein the counter substrate includes an overcoat layer at least in thedisplay region and a region provided with the sealing material, and thegrooves are formed in positions which are located in the region providedwith the sealing material and from which portions of the overcoat layerare removed by a partial or total thickness of the overcoat layer. 8.The liquid crystal display device of claim 1, wherein in a region of thearray substrate in which a first interconnect, a first insulating film,a second interconnect, and a second insulating film are sequentiallystacked and the grooves overlap the first interconnect when viewed inplan, a stopper layer formed in a layer identical with the secondinterconnect is provided between the first insulating film and thesecond insulating film.
 9. The liquid crystal display device of claim 8,wherein a transparent conductive film is provided on surfaces of thegrooves to cover at least the stopper layer.
 10. The liquid crystaldisplay device of claim 1, wherein the grooves including two to twentygrooves are arranged in parallel in the array substrate.
 11. The liquidcrystal display device of claim 2, wherein the grooves including two totwenty grooves are arranged in parallel in the counter substrate.
 12. Aliquid crystal display device comprising: an array substrate including afirst interconnect, a first insulating film, a second interconnect, anda second insulating film which are sequentially stacked on a substratebody; a counter substrate facing the array substrate; an annular sealingmaterial which is provided outside a display region and by which thearray substrate is bonded to the counter substrate; a liquid crystallayer in a region surrounded by the sealing material between the arraysubstrate and the counter substrate; alignment films each provided on asurface of a corresponding one of the array substrate and the countersubstrate facing the liquid crystal layer to extend outside the displayregion and to cover an area including the display region; and aplurality of grooves in the surface of the array substrate facing theliquid crystal layer in a region provided with the sealing material, thegrooves extending along the sealing material and being spaced apart fromeach other in a width direction of the sealing material, wherein part ofthe sealing material located from the midway portion of the sealingmaterial in the width direction thereof toward the display region fillssome or all of the grooves, and is in contact with the alignment layers,and part of the sealing material located from the midway portion of thesealing material in the width direction thereof in a direction away fromthe display region is directly in contact with the array substrate.